For complex disorders, the common genetic variants that contribute to risk have small effect sizes; hence, these variants individually have limited application in disease risk evaluation. However, common genetic variants can be used to calculate polygenic risk scores (PRS), which can be used to evaluate disease risks. PRS are weighted sums of risk alleles across the entire genome, and have shown promise in the identification of high-risk individuals (Abraham et al., 2019, Chatterjee et al., 2016, Craig et al., 2020, Khera et al., 2018, Khera et al., 2019, Niemi et al., 2018, Selzam et al., 2018, Torkamani et al., 2018). For example, in one study, the top 1%, 5%, 10%, and 20% of individuals with high PRS for coronary artery diseases had ORs of 4.83, 3.34, 2.89, and 2.55, respectively, for developing these conditions (Khera et al., 2018). Although some of their functions may be modified by epigenetic mechanisms, genetic variants cannot be changed by environmental factors; therefore, PRS provide a relatively unbiased estimation of genetic risk and may have utility in situations when family history or information on other
